Professionals operating under extreme conditions may find themselves in life threatening situations or even critical situations as part of their task. For example, soldiers in combat may be attacked and face injury from explosions, shrapnel, bullets, Improvised Explosive Devices (IED), and many other sources. The medical supplies offered at the point of injury within seconds or minutes of the injury are very limited, and generally not available. Instead, desired medical supplies are not available until an injured soldier is evacuated from the hostile location, which may not be for an extended period of time. However, administering certain medical assistance at the time of injury may save a patient's life, generally referred to as the “golden hour” by doctors. Other long term conditions may also be avoided such as those associated with traumatic brain injury (TBI). Other professionals within the military, search and rescue, first responders, homeland security, disaster relief and other humanitarian efforts may require the same need for transportable critical care supplies. Other non-emergency professionals may require immediate sources of oxygen, such as those that work in remote locations, including those of the oil and gas industry, researchers, mining, etc. Even recreational activities, such as mountain climbing or SCUBA diving, may put a person in a remote, and/or extreme environment requiring readily available, immediate medical supplies.
Serious and life-threatening medical emergencies will often cause oxygen to be depleted in the body creating a risk of cardiac arrest or brain damage. Therefore, oxygen is generally administered in emergency situations to prevent hypoxia, and other conditions. At a minimum, administering oxygen at the time of injury can greatly reduce the effects of shock usually accompanying an extreme medical emergency. Depleted oxygen conditions may also be present in extreme environments, such as high elevation, where the administration of oxygen may assist a person in reducing the effects of hypoxia, overcoming hypoxia, or enhance performance in the task executed in high elevation, or diminish and prevent other altitude related problems.
However, obtaining a sufficient oxygen supply within minutes of injury in remote locations, extreme conditions, and/or exceptional circumstances (such as battlefield conditions or remote mountain locations) is extremely difficult. The oxygen source must be brought safely to an injured person in a remote or hostile environment. Therefore, the oxygen source must be lightweight, transportable, and safe to carry and administer under extreme conditions and environments. Oxygen must be administered within a minimal amount of time under stressful conditions, with minimal preparation and easy activation. Oxygen must also be administered at a sufficient rate to start having any effect on the patient. Flow rates over 4 liters per minute (LPM) are necessary to have any beneficial medical impact on a patient, while 6 LPM or more are desired, and 8 LPM or more are preferred. The emergency conditions requiring oxygen administration may be spontaneous requiring oxygen to be administered immediately with little or no preparation of the dispensing device. However, the emergency condition may not occur at regular intervals, thus requiring the storage and transportation of the dispensing device for an extended period of time. Given the spontaneity of most situations or the potential remoteness of the storage and use locations, limited and no maintenance is desired.
The prior art recognizes a number of oxygen generators, including those as described in the following U.S. patents: U.S. Pat. No. 4,671,270; U.S. Pat. No. 4,342,725; U.S. Pat. No. 3,955,931; U.S. Pat. No. 5,750,077; U.S. Pat. No. 5,620,664; U.S. Pat. No. 7,371,350; U.S. Pat. No. 3,742,683; U.S. Pat. No. 3,868,225; U.S. Pat. No. 2,558,756; U.S. Pat. No. 3,565,068; and U.S. Pat. No. 3,580,250. However, these generators do not provide a sufficiently lightweight, handheld, portable solution to oxygen generation.
The ultimate challenge with chemical oxygen generators is that the reaction producing the oxygen is exothermic, and the external temperature of the canister containing the generator can reach temperatures as high as 500-600 degrees Fahrenheit (° F.) (260-316 C). Once the reaction is initiated, it cannot be stopped until the reactant is depleted. The longer the reaction lasts and possibly an extended time thereafter, the exterior temperature of the oxygen generator will continue to rise to a maximum temperature. Accordingly, even if some of the prior art publications provide solutions to portable oxygen generators, there are no products for truly handheld generators where the outside temperature is not of critical concern when in direct contact with the skin. Specifically, there are no solutions for providing a handheld long duration generator for oxygen production at high flow rates for rugged use in harsh environments and/or varied conditions.
Problems arise in insulating a canister containing the chemical reactants to produce oxygen, such that it is not an easy task to merely insulate an existing canister. Any additional material to insulate the canister must itself withstand the temperatures of the reaction and will add weight and bulk to the oxygen dispensing system. Therefore, it is easy to surpass the weight and/or dimensions of a generator that would be easily handled and transported. Insulating the exothermic reaction also traps the heat in the reaction area so that the temperature continues to increase to unacceptable levels. The increased temperature will increase the reaction rate of the chemical reactants and accelerate the generation of oxygen. Therefore, it is difficult to control the flow rate and provide an extended flow oxygen generator of sufficient flow rate under these conditions.
Known oxygen generation sources do not provide the combination of a safe, lightweight, transportable, reliable, maintenance free solution to medical grade oxygen generation of 99% oxygen by volume for use in extreme environments or harsh climatic conditions that is easily triggered under stressful conditions and operated in any orientation. They may require regular refilling, such as gaseous and liquid oxygen applications. Others require electricity and/or batteries that may not be available or reliable for an extended period of time. Others still may require mixing that increases the time until oxygen is administered and may prevent the device from being used at all if the environment is hostile and does not permit the requisite preparation conditions, operation temperatures, or operation orientations. Other problems encountered by the prior art oxygen generators include the unavailability in extreme conditions, such as severe dust storm, heavy rain, freezing conditions, snow, extreme desert heat, or high altitude. The devices may also have to operate in a given orientation, have limited shelf life, are too big and/or heavy for transport to remote locations, require logistical support, risk explosion, provide insufficient flow, or are not capable of clearing the Federal Drug Administration requirements for use.